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Relation between the norm of a vector and its components

Posted Jun 30, 2013, 4:03 p.m. EDT Low-Frequency Electromagnetics Version 4.3b 3 Replies

Nestor Bolaños Rodriguez
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Hi, i'd like to know the relation between the quantities normJ and the components of the vector J (Jr, Jphi, Jz). I have simulated a coil group domain driven by a current of 10A.

The components Jr and Jz are equal to zero. So the vector J should be J=(0,Jphi,0)

A vector norm in 3D is defined as norm(v)=sqrt(v1^2+v2^2+v3^2), i.e. the square root of the sum of the norm of its components. In the above mentioned case, I would expect normJ and the Jphi component to have the same value, but it doesn't happen.

Unfortunately I cannot find any explanation of the relation of these current density quantities in the documentation set. If somebody could enlight my mind, this would be much appreciated.

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3 Replies Last Post Jul 1, 2013, 4:54 a.m. EDT
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago Jun 30, 2013, 4:29 p.m. EDT

Nestor,

all the field quantities can be complex. However, the plots only show the real part of the complex number.

Cheers
Edgar

--
Edgar J. Kaiser
www.emphys.com
Nestor, all the field quantities can be complex. However, the plots only show the real part of the complex number. Cheers Edgar -- Edgar J. Kaiser http://www.emphys.com
Nestor Bolaños Rodriguez
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Posted: 1 decade ago Jun 30, 2013, 8:30 p.m. EDT
Thanks for the reply, just two more questions:

1. which of the both expressions (normJ , Jphi) represent the real value of the current density. I think its normJ but i'm not sure.

2. If you look at the Jphi plot, there are positive and negative values. Although only the real part of the current is shown. Do the positive and negative signs mean that the current is flowing in opposite directions?
Thanks for the reply, just two more questions: 1. which of the both expressions (normJ , Jphi) represent the real value of the current density. I think its normJ but i'm not sure. 2. If you look at the Jphi plot, there are positive and negative values. Although only the real part of the current is shown. Do the positive and negative signs mean that the current is flowing in opposite directions?
Edgar J. Kaiser Certified Consultant
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Posted: 1 decade ago Jul 1, 2013, 4:54 a.m. EDT

The norm is real and positive by its defintion, the Jphi component can be complex. And Jphi in your picture obviously goes in both directions, looks like eddy currents.

--
Edgar J. Kaiser
www.emphys.com
The norm is real and positive by its defintion, the Jphi component can be complex. And Jphi in your picture obviously goes in both directions, looks like eddy currents. -- Edgar J. Kaiser http://www.emphys.com

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